Adjustable cam multiple contact switch arrangement

ABSTRACT

A plurality of switch blocks are mounted in an interlocking stacked relationship between end plates mounted to a rotatable shaft. Cams are mounted on the shaft for rotation with the shaft and cams are springloaded against sprockets so that the cams can be moved to disengage the sprockets so that the cams can be angularly adjusted with respect to the shaft. Pairs of stationary contacts are mounted on each of the switch blocks and are electrically connected by movable contact bridging members. A pivot arm is mounted on each of the switch blocks and a roller on one end of each of the pivot arm rolls against a corresponding cam to cause the movable bridging members connected to the opposite end of the pivot arms to disengage the stationary contact as the cams rotate. The pivot arms may be adapted to cause the bridging members to engage and disengage the stationary contacts with a lateral, wiping motion. In addition, groups of cams may be interconnected in a specific angular relationship so that the cams be angularly adjusted as a unit with respect to the shaft.

Rogers et al.

[4 1 Dec.'3,1974

i 1 ADJUSTABLE CAM MULTIPLE CONTACT SWITCH ARRANGEMENT [75] Inventors: Edward ,1. Rogers, Chicago; David Evans, Palatine, both of I11.

[73] Assignee: S & C Electric Company, Chicago,

Ill.

22 Filed: Sept. 14, 1973 21 Appl. No.: 397,415

200/38 CA, 153 LB, 164 R, 168 K, 1 R, 27 R, 31 R; 74/568 R, 568 T [56] References Cited UNITED STATES PATENTS 2,943,161 6/1960 Fath 200/38 BA 2,978,553 4/1961 Bundy etal. 200/38 BA 3,099,728 '2/1963 Scheib, .lr 200/164 R X 3,204,051 8/1965 Blodgett 200/38 BA 3,221,117 11/1965 Simmons 200/38 BA 3,261,937 7/1966 McVicker 200/153 LB X 3,483,344 12/1969 Hermle 200/38 BA X 3,569,992 3/1971 Papa, Jr ZOO/3.8 BA 3,624,332 11/1971 Van Benschoten et al..... 200/164 R prose-0 I 3,678,225 7/1972 Hulterstrum 200/38 BA Primary Examiner James R. Scott Attorney, Agent, or FirmKirkland & Ellis [57] ABSTRACT A plurality of switch blocks are mounted in an interlocking stacked relationship between end plates mounted to a rotatable shaft. Cams are mounted on the shaft for rotation with the shaft and cams are springloaded against sprockets so that the cams can be moved to disengage the sprockets so that the cams can be angularly adjusted with respect to the shaft. Pairs ,of stationary contacts are mounted on each of the switch blocks and are electrically connected by movable contact bridging members. A pivot arm is mountedon each of the switch blocks and a roller on one end of each of the pivot arm rolls against a corresponding cam to cause the movable bridging members connected to the opposite end of the pivot arms to disengage the stationary contact as the cams rotate. The pivot arms may be adapted to cause the bridging members to engage and disengage the stationary contacts with-a lateral, wiping motion. In addition, groups of cams may be interconnected in a specific angular relationship so that the cams be angularly adjusted as a unit with respect to the shaft.

i 1 Claim, 12 Drawing Figures PATENTE}, DEC 3 I974 SHEET 1 BF 5 PAIENTEL 31974 3.852.542

sneer sor 5 ADJUSTABLE CAM MULTIPLE CONTACT SWITCH ARRANGEMENT BACKGROUND OF THE INVENTION sion. For example,-U.S. Pat. No. 3,508,179 Bernatt,

et al., illustrates a motor driven operator for high voltage switches utilizing such switches to provide the limit controls for the driving motor. The present invention is an improved switching arrangement which could be utilized to perform the switching operations disclosed in U.S. Pat. No. 3,508,179.

BRIEF SUMMARY OF THE INVENTION In accordance with the present invention a multiple contact switch arrangement comprises a shaft mounted for rotation having a plurality of cams mounted on the shaft for rotation with the shaft. Each of the cams has protrusions positioned around the periphery thereof. A plurality of support means are stationarily mounted with respect to the shaft adjacent to the shaft and stationary electrical contact means are mountedon each of the support means. Movable electrical contact means are movably mounted on each of the support means, and a pivot means pivotably mounted on each of the support means operably engages the cam and the movable contact means so that the pivot means moves the movablecontact means to electrically disengage may be varied by varyingthe number of support means stacked together. In addition, groups of the cams may be interconnected at a predetermined angular relationship so that the interconnected cams can be angularly adjusted as a unit with respect to the shaft. Further, the

A further object is to provide for manufacturing economy in that a variety of assemblies and variations can be made with a minimum number of total parts.

These and other objects, advantages and features of the present invention will hereinafter appear. but, for the purposes of illustrations, but not of limitation, exemplary embodiments of the present invention are illustatrated in the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevation view of a preferred embodimentof the present invention. 7 I

FIG. 2 is a cross-sectional partially fragmentary view taken substantially along line 2-2 in FIG. 1.

FIG. 3 is a cross-sectional'view taken substantially along line 3-3 in FIG. 1.

FIG. 4 is' a cross-sectional view taken substantially along line 44 in FIG. 1. FIGS. 5, 6, and 7 are partially-fragmentary views of a preferred embodiment of the present invention illustrating the opening and closing sequence of the movable contact bridging member.

FIG. 8 is an exploded perspective partially fragmentary view of one of the cam adjusting means of the present invention. v FIG. 9 is a top view of an alternative embodiment of a contact support block and contact configuration in accordance with the present invention. 7

FIG. 10 is a top view of one embodiment of the contact bridging member in accordance with the 'present invention.

FIG. 11 is a side view of the contact bridging member illustrated in FIG. 10.

FIG. 12 is a cross-sectional partially fragmentary view taken substantially along line 12- 12 in FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS With reference to FIG. 1, switch arrangement 10 comprises hexagonal shaped shaft 12 extending through the length of switch arrangement 10. Mounted at the upper end of shaft 12 is sprocket 14 held in position by set screw 16. Riding on and engaging sprocket 14 is drive chain 15 (shown in dotted lines connected to an operating means such as a motor) (not shown). Mounted beneath sprocket 14 are two indicating collars l8. Collars 18 are adjustable and can be lockedwith ,set screws 19 to indicate the end position of the pivot means may be adapted to cause the movable contact means to engage and disengage the stationary contact means' with a lateral wiping action to assure more reliableelectric'al connection. v Thus, it is a primary object of the present invention to provide a multiple contact switcharrangement having rotating adjustable cams to initiate-opening and closing sequencing. lt is'a further object of the present'invention toprovide a multiple contact switch arrangement having a high voltage switch or specific contact position, one for open and one for -closed. A bearing 20 is positioned through an opening in end plate 22 and a bearing 24 is positioned between end plate 22 and annular with reduced friction.

Mounted between end plates 22 and 34 by tie rods 35 are a plurality of switch support block assemblies 36.

With reference to FIG. 4, switch support block assemblies 36 comprise first and second switch blocks 38 and 40, which are substantiallyidentical except that second switch block 40 is substantially a reverse mirror replica of first switchblock 38. I

Mounted on a supporting flange 42 on first switch block 38 are first and second stationary contacts 44 and 46. Connected to stationary contacts 44 and 46 are threaded terminal shafts 45 which extend through supporting flange 42. Electrical conductors may be connected to terminal shafts 45 by appropriate nuts. A contactbridging member 48 is biased towards stationary contacts 44 and 46 by spring 50 so that contact bridging member 48 normally engages both stationary contacts and completes an electrical circuit the'rebetween. Contact bridging member 48 rides in a groove 52 formed in blocks 38 and 40 so that contacting bridging member 48 can move laterally substantiallyin adirection parallel to the axis of contacts 44 and 46.

Pivotally mounted to blocks 38 and 40 by pin 56 is pivot arm'54. One end of pivot arm 54 is connected to contact bridging member 48 by insulating bushing 58 which electrically isolates contact bridging member 48 from pivot arm 54. Rotably mounted to the opposite end of pivot arm 54 is follower roller 60. v

Mounted on shaft 12 immediately-below end plate 22 is first cam assembly 70 (see FIG. 1). First cam assem-,

bly 70 comprises hub 72 which is mounted on hexagonal tube 74'. Hexagonal tube 74 fits into a hexagonal shaped opening in hub 72 so that hub 72 can move laterally with respect to tube 74, but rotation of hub 72 causes hexagonal tube 74 ,to rotate. A collar 76 is mounted on tube 74 by set screw 78, and a spring 80 is positioned between collar 76 and hub 72so that hub 72 is biased in a downwardly direction against bearing 82 mounted on plate 84. Positioned immediately above bearing. 82, between bearing 82 and bearing 86, is annular ring 88 which-has a hexagonal opening foraccepting shaft 12 so that annular ring 88 rotates with hexagonal shaft 12.;Annular ring 88 has formed around the periphery thereof teeth 89 (see FIG. 8) which engage mating-teeth in cover 90 bolted to hub 72 by bolts 92. Hub 72 is adapted to be moved upwardlytagainst the spring 80 so that the teeth on ring 88 and cover 90 are disengaged so that hub 72-and tube 74 can be rotated relative to shaft 12.

Attached totube 74 are cams 94. Cams 94 are separated by spacers 96 and 98 so that cams 94 are retained inposition adjacent. to follower rollers 60 in pivot arms 54. Thus, cams 94 can be rotated relative to shaft 12 by causing hub 72 to be moved upwardly. against the their new position.

. Mounted immediately below plate 84 issecond cam assembly 100. Second calm assembly 100 is substanti'ally identical to first cam assembly 70 except that only cams 94a are adjusted'when M5102 is moved downwardly against spring 104 sothathexagonal tubes 106 can be" rotatedto angularly adjustcams' 94a with respect tosh'aft 12. The remaining cams 94b are not coni. nected to hexagonal tube 106 and may beindepen dently adjusted as .will hereinafter be described.

Positioned between cams 94b are spacers 110 and 112. Springs 114 are positioned around spacers 110 and hold cams 94b against spacers 112. Rings 116 are mounted on shaft 12 against'spacers 1-12,so that rings 116 turn with shaftlZ. Teeth 117 are formed on the-periphery of ring 116, (see FIG. .12) that engage mating teeth 97 on an interior opening in cam 94b. Thus,

springs '114. normally hold cams 94b in engagement withring 116' so that cams 94b rotate withshaft However by moving cams 94b away from rings 116 so that the teeth 117 and 97 disengage, the cams can be rotated with respect to shaft 12 to angularly adjust each of the cams with respect to shaft 12. Consequently, each of the cams 94b can be independently adjusted to fix the angular position at which the protrusions 94 on cams 94b engage follower roller 60 attached to pivot arm 54, and thus, the angular position of shaft 12 at which contact bridging member 48 disengages stationary contacts 44 and 46.

With respect to FIGS. 5, 6, and 7, the opening and closing action of contact bridging member 48with stationary contacts 44 and 46 is shown. Formed in the end of pivot arm 54 is channel 55 which is formed at an angle with respect to the center line of pivot arm 54. When in an open position, as illustrated in FIG. 5, the axis of the contact point of bridging member 48 is disposed to a position parallel to the center axis of stationary contacts 44 as denoted by the separation D shown in FIG. 5. As cam 94 rotates and contact bridging member 48 approaches stationary contacts 44 and 46, contact bridging member 48 moves in a direction parallel to the center axis of stationary contacts 44. However, as contact bridging member 48' comes into contact with stationary contacts 44 and 46, the angular relationship of channel 55 causes contact bridging member 48 to move laterally with respect to stationary contacts 44 and 46 so that contactbridging member 48 is moved laterally across stationary contacts with a wiping action until contact bridging member 48 is in the position shown in FIG. 7. In this position, the. center axis of stationary contacts 44 and 46 coincides increases the reliability of theelectrical connection between the contacts.

. FIGS. 9,10 and 11 illustrate an alternative.embodi-- ment of the switch support block assemblies of the present invention. This embodiment issubstantially'the same as that illustrated in FIG. 4 except that the struc ture of the contactbridging member 120 and the pivot arm 122 has been modified. Pivot arm 122 is pivotably mounted to switch block 124.bypin.126..A.follower roller 128. is mounted to the endof pivot arm l22 bypin' 130. A flange 132 is formed ontheend of pivot arm 122and folded over the top of follower roller 128 so that pin 130 is supported at both ends to provide greater stability for follower roller-1'28. A channel 134 is formed in the opposite endof pivot arm"122' to re ceive and "guide insulating bushing 136. connected to contact bridging memver 120.'The angular relationship of channel 134 is such that there'is no wiping action whencontact bridging member 120 engages and disengages thestationary, contact 138. Spring is biased to urge contact bridging member 120 against'statio'nary contacts 138.

Thestructure of contactbridging memberj120=is il lustrated in FIGS. 10 and 11. Contact bridging member 120 is formed from a'single piece of metal and folded to provide solid unitary construction. Tabs 142 can be inserted into spring 140 so that-spring140 remains in engagement with contact bridging member 120 and guide tabs 144 guide contact bridging member 120 along groove 146 formed in switch block 124.

As illustrated in FIG. 1, switch support block assemblies 36 are designed to be stackable in an interlocking relation one on top of the other so that any number of switch support block assemblies 36 may be mounted along shaft 12. The only limitation to the number of switch block assemblies that may be so mounted is the length of the shaft 12, and an increased number of switch block assemblies may be provided by providing a longer shaft 12. Consequently, the present invention provides greater flexibility in varying the total number of switch contacts available for switch operations than prior art arrangements.

Further, the present invention provides flexibility in the adjustment of the angular position at which the various contact bridging members engage and disengage the stationary contacts. As previously pointed out, first cam assembly 70 and second cam assembly 100 permit simultaneous adjustment of a plurality of earns 94 and 94a that have a fixed angular relationship with respect to each other. in addition, cams 94b are provided which are independently adjustable so that each of the cams 94b can be respectively adjusted. Thisadjustment feature is especially advantageous when adjusting a motor operated high voltage switch operator to cause the motor to be stopped at the end of an opening or closing motion. Movement of the set .of associated cams will easily change the stopping positions (advance or retard) and those contacts whose functions are required to be associated with the particular end position v of the high voltage switch automatically maintain their correct relationship. Other switch functions (indicator lights, interlocks, etc.).may be controlled by the other cams, and their relative operating positions are not 14 (connected to a motor or other operating mechanism not shown) will produce a fixed continuous sequence of operation. However, if at any time it is desired to change the sequence of operation of the various switches, the various cams can be easily adjusted as previously described.

An additional advantage of the present invention is illustrated in FIGS. 5, 6, and 7. The contact wiping action illustrated in FIGS. 5, 6, and 7 helps to prolong the contact life and assure reliable operation and electrical contact for an extended period of time.

Further, if many time it is desirable to replace or repair any of the switch-block assemblies 36, the switch block assemblies can be easily removedwithout affecting the adjustment of the cams by merely removing tie rods 35 and sliding the switch support block assemblies 36 from between end plate 22 and end plate 34. Come quently, it is not necessary to totally disassemble switch arrangement 10 to beable. to replace individual switch support block assemblies 36.

it should be further understood that various changes, modifications and variations of the subject invention may be taken without departing from the spirit and scope of the present invention as defined in the appended claims.

We claim:

1. A multiple contact switch arrangement comprising:

a first end plate;

a second end plate;

a shaft removably mounted for rotation between said first and second end plates; means for rotating said shaft;

a' plurality of switch support blocks removably.

mounted against one another between said end plates in a stacked relationship adjacent to said shaft, said switch support blocks having coincident openings therethrough parallel to said shaft;

removable mounting means positioned through the openings in said switch block for disengageably mounting said switch support blocks between said first and second end plates;

a first set of cams removably mounted on said shaft for rotation with said shaft, said first set of cams having protrusions positioned on the periphery thereof;

a second set of cams removably mounted on said shaft for rotation .with said shaft, said second set of cams having protrusions positioned on the periphery thereof,

a pair of stationary contacts mounted on each of said support blocks;

a plurality of movable contact bridging members each slidably mounted on a respective support block for electrically connecting a respective pair of stationary contacts;

spring means for biasing said movable contact bridging members toward said stationary contacts;

a plurality of cam followers, each pivotably mounted on a respective support block, each of said cam followers having a first end engaging 'and following a respective cam and a second end connected to a respective movable contact bridging member so that when said first end engages the protrusion on its respective cam, said cam follower moves its respective contact bridging member to electrically disengage the respective stationary contacts;

first adjusting means for permitting adjustment of the ary contacts can be independently predetermined.

' l k k 

1. A multiple contact switch arrangement comprising: a first end plate; a second end plate; a shaft removably mounted for rotation between said first and second end plates; means for rotating said shaft; a plurality of switch support blocks removably mounted against one another between said end plates in a stacked relationship adjacent to said shaft, said switch support blocks having coincident openings therethrough parallel to said shaft; removable mounting means positioned through the openings in said switch block for disengageably mounting said switch support blocks between said first and second end plates; a first set of cams removably mounted on said shaft for rotation with said shaft, said first set of cams having protrusions positioned on the periphery thereof; a second set of cams removably mounted on said shaft for rotation with said shaft, said second set of cams having protrusions positioned on the periphery thereof; a pair of stationary contacts mounted on each of said support blocks; a plurality of movable contact bridging members each slidably mounted on a respective support block for electrically connecting a respective pair of stationary contacts; spring means for biasing said movable contact bridging members toward said stationary contacts; a plurality of cam followers, each pivotably mounted on a respective support block, each of said cam followers having a first end engaging and following a respective cam and a second end connected to a respective movable contact bridging member so that when said first end engages the protrusion on its respective cam, said cam follower moves its respective contact bridging member to electrically disengage the respective stationary contacts; first adjusting means for permitting adjustment of the angular position of said first set of cams with respect to the angular position of said shaft as a unit so that the angular position of said shaft at which each of said respective contact bridging member disengages its respective stationary contacts can be predetermined; and second adjusting means for permitting adjustment of the angular position of each cam of said second set of cams independently with respect to the angular position of said shaft so that the angular position of said shaft at which each of said respective contact bridging members disengages its respective stationary contacts can be independently predetermined. 